1. Field of the Invention
This invention relates to a reciprocating internal combustion engine and, more particularly, to a turbo-supercharger for pressuring the suction air for the engine to thereby increase the charging efficiency and improve engine output.
2. Description of the Prior Art
There is a known turbo-supercharger for reciprocating internal combustion engines in which a turbine is rotated by the exhaust energy from the engine to actuate a compressor, which then causes the suction air to be pressurized so as to increase the charging efficiency and thereby improve engine output. In such an internal combustion engine, a pulsation of pressure occurs in a suction passage due to the intermittent opening and closing operations of a suction valve. The pulsation of pressure affects the outlet of the compressor to cause a so-called "surging phenomenon", which results in a decrease in the flow rate of suction air and, thus, engine output. It is known that, in order to eliminate the above-mentioned inconveniences, a prechamber having a predetermined capacity is provided in that portion of the suction passage which is between the compressor and a throttle valve, the pulsation of pressure occuring in the suction passage being thereby damped. However, it is difficult for the turbo-supercharger, to which only such a pre-chamber is added, to attain an improvement in engine output with respect to all operational regions of the engine without adversely affecting the controlling of an operation of the engine and the performance thereof and without causing a surging phenomenon in the compressor.